Explosive bullet



Patented Got. 26, 1948 UNITED STATES PATENT OFFICE (Granted under theact of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) '7Claims.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes without the payment to me ofany royalty thereon.

This invention relates to explosive projectiles, and more particularlyto the fuse mechanism of such projectiles. One of the objects ofinvention is to devise a fuse mechanism which will be simple inoperation and inexpensive to produce and which will positively detonatethe explosive charg upon impact of the projectile with the target, andwhich is implemented with arming means rendering the projectile safewhile in its cartridge case and while traversing the bore of the firinggun. A further object of invention is to provide means for destroyingthe projectile in the event it misses the target.

For the attainment of the foregoing and such other objects as may hereinappear or be pointed out I have shown one embodiment of my invention inthe accompanying drawing, wherein:

Fig. 1 is a longitudinal section of the improved explosive projectile,shown held in place of its cartridge shell (in unarmed condition) Fig. 2is a partial longitudinal section showing the fuse parts in armed andfired condition; and

Fig. 3 is a cross section through the fuse mechanism, on the line 33 ofFig. 1.

The improved explosive projectile is made up of two main parts, viz., aforward jacket member In and a rear thimble member 20. Forward jacketmember ID is provided at its tapered forward end with internal screwthreads in which is screwed a plug fitting I I to close that end. Therear, widened end of jacket member I is open. The rear end of thethimble member of the projectile is likewise open, but its forward endis closed by a partition 2| of considerable thickness compared to thethin walls of members I0 and 20. The rear open end of jacket member I0is secured to the thimble member 20, or rather to its partition 2!. sothat the partition forms a closure for the forward jacket member I0.Member'IO is secured, as by brazing or other joining process, to anannular fiange 22 provided on partition 2 I.

The wall of forward member ID constitutes the gilding metal jacket ofthe projectile which serves to take the rifiing when fired. Near therear end of the forward or jacket member ID is provided an annulargroove I2 in which the leading edge of the cartridge case 9 is crimpedor rolled. The walls of jacket member In and the partition 2| of rearmember 20 constitute a container for the explosive charge 8, plugfitting I I being unscrewed at the mouth of the container during thefilling operation. A central passage is prepared in the explosive charg8 for a firing pin 3 i. Plug fitting II is likewise provided with acentral passage I3 for the firing pin. Firing pin 3i extends from a nosepiece to a point close to partition 2I of rear member 20, the topsurface of partition 2| being also pierced by a central hole 29 for thepointed end of the firing pin.

Disposed diametrically in the partition 2| is a drilled hole or bore 23which is closed at one end by wall 24 and provided at its open end withinternal threads in which is screwed a plug 25. Plug 25 is provided witha central hole 26, see esp. Fig. 2, through which is passed a pin 21having a. tapered head which is seatable in a countersunk mouth providedon the outside of plug 25.

The function .of pin 2'! is to normally maintain the detonating slide inunarmed position, which is rightward of firing pin 3i, see Fig. 1.Detonating slide 40 is of cylindrical shape and is slidably received inthe bore 23 of the partition 2|. To prevent rotation of slide All it isprovided with a pin 48 slidably received in a keyway 28 in partition 2I. Slide all is provided with a cavity 4| open at the top, whichcontains the primer detonator. A compression spring 32 interposedbetween the detonator slide 40 and the end wall 24 of bore 23, tends tourge the slide leftwardly to bring-detonator cavity 4| under'the centralhole 29 of the partition 2I and inalignment with firing pin 3I. However,this leftward urgency of the spring 42 to move the detonator slide toarming position is normally blocked by the pin 27. Arming pin 21 ispointed at its end to be received in a punch hole 41 provided indetonator slide 40. When the projectile is still held in its cartridgecase as it is in Fig. 1, the head of arming pin 2'! bears against thecartridge case 9 and thus interposes itself as a positive stop betweenthe car- 'tridge case wall and the detonating slide 40',

maintaining the slide in disarming position with detonator cavity M tothe right of firing pin 3|. When the projectile leaves its cartridgecase but while it is still within the gun barrel, the bore itself servesas a stop as the head of the arming pin 21 rides along the gun bore. Thearming pin becomes free to be moved leftwardl out of the projectile,permitting detonator slide 413' to move leftward to arming position,Fig. 2, only when the projectile has passed beyond the muzzle of thegun.

Interposed between the nose piece 39 and the plug fitting II is acompression spring 32 which 3 urges firing pin 3| in a forward directionaway from the detonator slide 46. Upon impact of nose piece 36 with thetarget, the firing pin is moved rearwardly to strike the primerdetonator M, Fig. 2, which is in arming position. The rear of nose piece30 is in the form of a skirt 33 which provides'a covering for spring 32.The edge of skirt 33 is flanged inwardly, the flange lip 34 thus formedabuts against a shoulder i4 formed in the plug fitting I I, which servesas a stop to the forward movement of nose piece 30 under urgency ofspring 32. As clearly seen in Fig. 1 plug fitting l I has an annulargroove l5 encircledby the flange lip 34, and of suflicient length toprovide for sliding movement of said lip 34 when nose piece 39 contactsthe target.

The rear member 20, open at its rear end as described, contains tracercomposition l.

The

improved projectile is capable of self-destruction when it misses theintended target. This feature of self-destruction is achieved by thetracer composition i, For this purpose the rear side of partition 2| isprovided with a central aperture 2912 opening into the bore 23, and thefloor of the detonator cavity 4| is provided with a small hole 41a.Hence when slide All has been moved by spring 42 to arming position, asshown in Fig. 2, the hole Na in the detonator cavity of the slide willbe aligned with the'c'entral aperture 290. in partition 21. In the eventthat the projectile misses the intended target, the tracer composition Iwill continue to burn until it reaches aperture 29a whereupon the primerdetonator 4| will be ignited by the tracer flame through the apertures29a and Ma, and set off explosive 8 to destroy the projectile.

I claim:

1. An explosive projectile comprising, in combination, a jacket memberprovided at its open forward end with internal threads and open at itsrear end, a thimble member closed at its forward end by a partition ofsubstantial thickness and open at'its rear end, the said partition beingprovided with an annular rim for securement of the said open rear of thejacket member, a plug fitting provided with external threads forscrewing into the said threaded forward end of the jacket member andprovided with a central passage, a firing pin extending through the saidcentral passage to a point close to the said partition of the thimblemember, explosive charge filling the said jacket member, a nose piecesecured to the forward end of the firing pin extending beyond the saidplug fitting and provided with a rearwardly extending skirt having aninwardly directed flange, the said plug fitting having an annular groovereceiving the said skirt flange for a limited extent of sliding movementof the firing pin and its said nose piece, a compression springinterposed between the said nose piece and the plug fitting normallymaintaining the firing pin in forward position, the said partition ofthe thimble member being provided with a diametrically oriented boreclosed at one end and provided with internal threads at its open end, aslide member within the said bore provided with a punch hole in its endfacing the mouth of the bore and with a cupped receptacle near its otherend, primer detonating charge filling the said receptacle, the forwardface of the partition of the thimble member being provided with acentral aperture aligned with the said firing pin and opening into thesaid bore, a compression spring interposed between the said slidingmember and the closed end of the'bore urgingthe said sliding membertowards the mouth of the bore to bring the said detonator receptacleinto alignment with the said firing pin aperture of the partition, ascrew plug for closing the mouth of the bore provided with a centralhole and countersunk in its outer face, an arming pin extending throughthe said plug hole and pointed to be received in the saidpunch hole ofthe detonator slide member and provided with a head seated in the saidcountersunk opening of the plug, the said arming pin being adapted byabutment of its said head with the cartridge shell and with the gun boreto hold the detonator slide in disarming the said bore, the bottom ofthe detonator receptacle being provided with a small aperture alignablewith the said rearward aperture of the partition when the detonatorslide is in arming position, tracer charge filling the said thimblemember and adapted upon burning to the partition when the projectile hasmissed its target, to ignite the detonator through the aligned partitionaperture and the detonator receptacle aperture to destroy theprojectile.

2. An explosive projectile comprising, in combination, a jacket memberprovided at its open forward. end with internal threads and open at itsrear end, a thimble member closed at its forward end by a partition ofsubstantial thickness and open at its rear end,'the said partition beingsecured to the said open rear of the jacket member, a plug fittingprovided With external threads for screwing into the said threadedforward end of the jacket member and provided with a central passage, afiring pin extending through the said central passage to a point closeto the said partition of the thimble member, explosive charge fillingthe said jacket member, a nose piece secured to the forward end of thefiring pin extending beyond the said plug fitting and provided with arearwardly extending skirt having an inwardly directed flange, the saidplug fitting having an annular groove receiving the said skirt flangefor a limited extent of sliding movement of the firing pin and its saidnose piece, a compression spring interposed between the said nose pieceand the plug fitting normally maintaining the firing pin in forwardposition, the said partition of the thimble member being provided with adiametrically oriented bore closed at one end, a slide member within thesaid bore provided with a cupped receptacle, primer detonating chargefilling the said receptacle, the forward face of the partition of "thethimble member being provided with a central aperture aligned with thesaid firing pinand opening into the said bore, a compression springinterposed between the said slidin member and the closed end of the boreurging the said sliding member towards the mouth of the bore to bringthe said detonator receptacle into alignmentwith the said firing pinaperture of the partition, an arming pin inthe said bore adapted byabutment with the cartridge shell and with the gun boreto holdthedetonator slide in disarmingposition with-the detonator receptacle outof alignment with the firing pin, the rearward face of the partition ofthethim'ble member being provided 'with a central aperture opening intothe said bore, the bottom of the detonator receptacle being providedwith a small aperture alignable with the said rearward :aperture of thepartition when'th'e detonatorvs'lide is in arming position, tracercharge filling the said thimble member and adapted upon burning to thepartition when the projectile has missed its target, to ignite thedetonator through the aligned partition aperture and the detonatorreceptacle aperture to destroy the projectile,

3. An explosive projectile comprising, in combination, a jacket memberprovided at its open forward end with internal threads and open at itsrear end, a partition of substantial thickness closing the rear end ofthe jacket member, a plug fitting provided with external threads forscrewing into the said threaded forward end of the jacket member andprovided with a central passage, a firing pin extending through the saidcentral passage to a point close to the said partition of the thimblemember, explosive charge filling the said jacket member, a nose piecesecured to the forward end of the firing pin extending beyond the saidplug fitting and provided with a rearwardly extending skirt having aninwardly directed flange, the said plug fitting having an annular groovereceiving the said skirt flange for a limited extent of sliding movementof the firing pin and its said nose piece, a compression springinterposed between the said nose piece and the plu fitting normallymaintaining the firing pin in forward position, the said partition ofthe thimble member being provided with a diametrically oriented boreclosed at one end, a slide member within the said bore provided with acupped receptacle, primer detonating charge filling the said receptacle,the forward face of the partition of the thimble member being providedwith a central aperture aligned with the said firing pin and openinginto the said bore, a compression spring interposed between the saidsliding member and the closed end of the bore urging the said slidingmember towards the mouth of the bore to bring the said detonatorreceptacle into alignment with the said firing pin aperture of thepartition, an arming pin in the said bore adapted by abutment with thecartridge shell and with the gun bore to hold the detonator slide indisarming position with the detonator receptacle out of alignment withthe firing pin.

4. An explosive projectile adapted for insertion in a cartridge casecomprising, in combination, a jacket provided with a central passage atits nose end and open at its tail end, an explosive charge in theforward end of the jacket and a tracer charge in the tail end, apartition separating said charges, a detonator slide in the partitionand having a detonator therein, a firing pin extending through said nosepassage to a point close to the detonator slide, an impact head carriedby the forward end of the firing pin, spring means normally holding thefiring pin away from the detonator, spring means in the partitionnormally urging the slide to a position to bring the said detonator intoline with the firing pin, an arming pin arranged to be interposedbetween the detonator slide and a cartridge case to hold the detonatorin the slide out of alignment with the firing pin before firing andthereafter engaging the barrel of the gun to hold the slide in suchposition until the projectile clears the gun barrel, means carriedpartly by the slide and partly by the partition whereby communication isestablished between the explosive charge in the projectile and thetracer charge, so that the explosive charge is ignited by the tracercharge should the target be missed, to destroy the projectile.

5. An explosive projectile adapted for insertion in a cartridge case, atransverse bore adjacent the tail end of said projectile, a detonatorslide in said bore having a detonator therein, a firing pin extendingthrough the nose of the projectile to a point adjacent the slide, meansfor normally holding said firing pin away from said slide, said pinbeing adapted to be operated upon impact to strike the detonator, springmeans in the bore normally urging the detonator into alignment with thefiring pin, and an arming pin with one end in engagement with slide andthe other constructed and arranged for engagement with the cartridgecase before firing, and thereafter engaging the barrel of the gun tohold the slide in unarmed position until the projectile clears the gunbarrel.

6. An explosive projectile and cartridge case comprising, incombination, a jacket secured to said cartridge case, a detonator slidetransversely disposed in said jacket, and having a detonator therein, afiring pin longitudinally disposed in the jacket and extending to apoint close to said detonator slide, spring means urging said detonatorslide to a position to bring the detonator therein in alignment with thefiring pin, and a freely slidable arming pin in said jacket interposedbetween the detonator slide and the cartridge case to maintain thedetonator slide in unarmed position before firing, and to thereafterengage the barrel to hold the slide in such position until theprojectile is clear of the gun barrel.

7. An explosive projectile comprising, in combination, a jacket havingan opening in its forward end for the passage of the firing pin, and anopen tail end, a partition adjacent the open end of the jacket, anexplosive charge in the jacket in advance of the partition and a tracercharge in the rear of said partition, a detonator-containing slide insaid partition, a firing pin in said passage and extending to a pointclose to the detonator and arranged to strike said detonator upon impactof the projectile, expendible means for holding the detonator normallyout of line with said pin, means carried partly by the slide and partlyby the partition whereby communication is established between thedetonator and the tracer charge so that the explosive charge will beignited by the tracer charge should the target be missed, to destroy theprojectile.

SHERMAN A. SCI-IATZ.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 672,826 Gathmann Apr. 23, 19011,518,247 Brayton Dec. 9, 1924 1,992,926 Towner Feb. 26, 1935 2,118,062Woodberry May 24, 1938

